The subject of the present invention is a fluidic machine whose swept volume is variable as a function of the pressure. The generic expression “fluidic machine” is to point out that the machine can be a pump, whose swept volume varies as a function of the outlet deliver pressure, or a motor, whose swept volume varies as a function of the inlet feed pressure. The invention is foreseen to be particularly applied to hydraulic machines, however it can be applied to pneumatic machines too.